1. Field of the Invention
The present invention relates to a radio-controlled timepiece correcting a time instant on the basis of a time code received by a radio, and relates especially to an analog radio-controlled timepiece analog-displaying the time instant by time instant hands.
2. Description of the Related Art
From olden times, there is utilized the radio-controlled timepiece receiving a standard radio signal including the time code denoting a present time instant by the radio, thereby correcting the time instant in an inside of the radio-controlled timepiece.
When performing a time instant correction, since it is not limited that a time code signal included in the standard radio signal can not be necessarily received normally, in order to inform whether or not the time instant correction is normally performed by normally receiving the time code, there is constituted such that it is notified to a user by stopping a second hand at a specified position, in which there is a yes/no display of a success in a last time reception, bypress-operating an operation switch other than a crown.
Further, in a timepiece in which there is attached an optical element such as liquid crystal or LED, there is constituted such that the yes/no in the last time reception is displayed by the optical element.
However, in the above radio-controlled timepiece, since an exclusive component such as operation switch or optical element is used in order to display the yes/no in a time code reception, there is an issue that the constitution becomes complicated and becomes expensive.
As a radio-controlled timepiece capable of solving this issue, there is an analog radio-controlled timepiece which has a crown for correcting the time instant and one motor for driving time instant hands (a second hand, an hour hand, a minute hand), and in which the time instant hands are driven by the above motor through train wheels, wherein, in order to inform whether or not the time code included in the standard radio signal was normally received, it is displayed by changing a hand motion interval of the second hand in a case where the time code could be normally received and a case where there failed in the reception (e.g., refer to Patent Documents JP-A-2001-159689 Gazette (Paragraphs [0021]-[0026], FIG. 1, FIG. 2) and JP-A-2003-004873 Gazette (Paragraphs [0009]-[0028], FIG. 1-FIG. 4)).
That is, in the invention described in each of the Patent Documents 1 and 2, there is made such that the user can recognize the fact that the reception of the time code failed by performing, in the case where the reception of the time code failed, a hand motion interval different from an ordinary hand motion interval, e.g., the second hand performs a hand motion (two-second hand motion) by gathering for 2 seconds every time 2 seconds elapse, or performing a continuous hand motion at an ordinary time instant display time and a step hand motion at a reception failure time.
FIG. 7 is a timing diagram of the 2-second hand motion in a conventional radio-controlled timepiece. As shown in FIG. 7, under a state failed in the time code reception, every time a time elapses 2 seconds, the second hand is driven by gathering two times on the basis of drive signals OUT 1 and OUT 2. By this, the user can recognize whether or not there failed in the reception of the time code.
However, since the special hand motion such as the above 2-second hand motion is continued till a next reception succeeds, there is an issue that the user always feels a sense of discomfort when reading the time instant. Further, there is an issue that it is impossible to know how much failed continuously in the past in the reception of the time code while accumulating.